Main Page

From BIOL 2P96 Jan 2013 Group 03

Revision as of 10:03, 21 March 2013 (edit) Cr11gi (Talk | contribs) m (→Truffles) ← Previous diff		Revision as of 10:16, 21 March 2013 (edit) (undo) Cr11gi (Talk | contribs) m (→Agriculture) Next diff →
Line 102:		Line 102:
	===Agriculture===		===Agriculture===
	The majority of higher plants exist in some sort of symbiotic relationship with mycorrhiza connections with either Endomycorrihza, Ectomycorrhizal fungi. The most widely used fungi in agricultural development are part of the endomycorrihza family, many agricultural companies sell inoculant for use in fields such as [http://en.wikipedia.org/wiki/Glomus_intraradices Glomus intraradices]. This is especially important in agriculture as many farmers employ fungi inoculation of the root system a key part of development of their crops. These fungi improve nutrient uptake and help to optimize [http://en.wikipedia.org/wiki/Fertilizer fertilizer], water uptake and can also restore degraded soil, cutting a farmers costs <ref> Kurle, J.E and F.L. Pfleger, 1994. The Effects of Cultural Practices and Pesticides on VAM Fungi. In: Mycorrhizae and Plant Health, Pfleger, F.L. and R.G. Linderman (Eds.). APS Press, St. Paul, Minnesota, USA., pp: 101-131 </ref>. Endomycorrihza fungi can increase water absorption and can absorb all 15 essential micro and macro nutrients essential for plant growth and development especially in areas of low soil quality <ref> Lester, D., 2009. Buying and applying mycorrhizal fungi. Max. Yield. USA., pp: 126-131 </ref> . Mycorrhizae fungi can also provide disease protection against necrotrophic competing fungi, insects and increased resistance to salinity and heavy metals in the soil <ref> Gange, A.C., D.E. Lindsay and L.S. Ellis, 1999. Can arbuscular mycorrhizal fungi be used to control undesirable grass Poa annua on golf courses. J. Applied Ecol., 36: 909-919 </ref> . Many modern farming practices however do not encourage the use of endomycorrihza fungi, many modern practices are actually detrimental to soil fungal population. The use of [http://en.wikipedia.org/wiki/Biocides biocides], [http://en.wikipedia.org/wiki/Monocultures monocultures], constant tilling and high amounts of fertilizer in the soil can have negative impacts on many endomycorrihza communities <ref> Kabir, Z., I.P. O'Halloran, J.W. Fyles and C. Hamel, 1998. Dynamics of the Mycorrhizal symbiosis of corn (Zea mays L.): Effects of host physiology, tillage practice and fertilization on spatial distribution of extra-radical mycorrhizal hyphae in the field. Agric. Ecosyst. Environ., 68: 151-163 </ref> . In an example of this a study was conducted in a monoculture soybean field with high [http://en.wikipedia.org/wiki/Fertilizer fertilizer] use, it was noted that high levels of [http://en.wikipedia.org/wiki/Phosphorus phosphorous] from constant [http://en.wikipedia.org/wiki/Fertilizer fertilization] was seen to inhibit endomycorrihza infection. Large [http://en.wikipedia.org/wiki/Summer_fallow summer fallow] periods associated with monocultures in which the land is left deliberately bare were seen to decimate endomycorrihza, which cannot survive without a host plant <ref> Ezawa, T., K. Yamamoto and S. Yoshida, 2000. Species composition and spore density of indigenous vesicular-arbuscular mycorrhizal fungi under different conditions of P-fertility as revealed by soybean trap culture. Soil. Sci. Plant Nutr., 46: 291-299 </ref> .		The majority of higher plants exist in some sort of symbiotic relationship with mycorrhiza connections with either Endomycorrihza, Ectomycorrhizal fungi. The most widely used fungi in agricultural development are part of the endomycorrihza family, many agricultural companies sell inoculant for use in fields such as [http://en.wikipedia.org/wiki/Glomus_intraradices Glomus intraradices]. This is especially important in agriculture as many farmers employ fungi inoculation of the root system a key part of development of their crops. These fungi improve nutrient uptake and help to optimize [http://en.wikipedia.org/wiki/Fertilizer fertilizer], water uptake and can also restore degraded soil, cutting a farmers costs <ref> Kurle, J.E and F.L. Pfleger, 1994. The Effects of Cultural Practices and Pesticides on VAM Fungi. In: Mycorrhizae and Plant Health, Pfleger, F.L. and R.G. Linderman (Eds.). APS Press, St. Paul, Minnesota, USA., pp: 101-131 </ref>. Endomycorrihza fungi can increase water absorption and can absorb all 15 essential micro and macro nutrients essential for plant growth and development especially in areas of low soil quality <ref> Lester, D., 2009. Buying and applying mycorrhizal fungi. Max. Yield. USA., pp: 126-131 </ref> . Mycorrhizae fungi can also provide disease protection against necrotrophic competing fungi, insects and increased resistance to salinity and heavy metals in the soil <ref> Gange, A.C., D.E. Lindsay and L.S. Ellis, 1999. Can arbuscular mycorrhizal fungi be used to control undesirable grass Poa annua on golf courses. J. Applied Ecol., 36: 909-919 </ref> . Many modern farming practices however do not encourage the use of endomycorrihza fungi, many modern practices are actually detrimental to soil fungal population. The use of [http://en.wikipedia.org/wiki/Biocides biocides], [http://en.wikipedia.org/wiki/Monocultures monocultures], constant tilling and high amounts of fertilizer in the soil can have negative impacts on many endomycorrihza communities <ref> Kabir, Z., I.P. O'Halloran, J.W. Fyles and C. Hamel, 1998. Dynamics of the Mycorrhizal symbiosis of corn (Zea mays L.): Effects of host physiology, tillage practice and fertilization on spatial distribution of extra-radical mycorrhizal hyphae in the field. Agric. Ecosyst. Environ., 68: 151-163 </ref> . In an example of this a study was conducted in a monoculture soybean field with high [http://en.wikipedia.org/wiki/Fertilizer fertilizer] use, it was noted that high levels of [http://en.wikipedia.org/wiki/Phosphorus phosphorous] from constant [http://en.wikipedia.org/wiki/Fertilizer fertilization] was seen to inhibit endomycorrihza infection. Large [http://en.wikipedia.org/wiki/Summer_fallow summer fallow] periods associated with monocultures in which the land is left deliberately bare were seen to decimate endomycorrihza, which cannot survive without a host plant <ref> Ezawa, T., K. Yamamoto and S. Yoshida, 2000. Species composition and spore density of indigenous vesicular-arbuscular mycorrhizal fungi under different conditions of P-fertility as revealed by soybean trap culture. Soil. Sci. Plant Nutr., 46: 291-299 </ref> .
-	<videoflash>XOaNAsau5F0</videoflash>	+	<videoflash>YDt2CMeIi6c#!</videoflash>
	<videoflash>5UXqeHexSog</videoflash>		<videoflash>5UXqeHexSog</videoflash>
	====Organic Farming====		====Organic Farming====

---

Revision as of 10:16, 21 March 2013

Introduction to Mycorrhiza

"Mycor" - "rhiza" is derived from the Greek words meaning "fungus" - "root" ^[1]. This symbiotic relationship occurs underground between a fungus and the root system of vascular plants. Mycorrhiza colonize in host plant root systems either intracellularly(endomycorrhiza) or extracellularly(ectomycorrhiza). It is possible upon invasion that a weakly pathogenic relationship is established, and has been studied infrequently upon these rare occasions^[2]. However, commonly upon invasion a mutualistic relationship is established in which hundreds of thousands of fungal hyphael branches are formed from the vegitative mycelium, and extend outwards into the soil. Nutrients are often depleted in areas directly around plant roots, thus by Mycorrhiza extending the root zone over a large area nutrient uptake of water, nitrogen, and phosphorous is increased. In return, in order to provide root growth the host plant provides the mycorrhiza with the necessary carbohydrates such as glucose and sucrose ^[3].

Shows Ectomycorrhiza (extracellular) symbiosis with a plant root [4]

Shows Endomycorrhiza(intracellular) symbiosis with a plant root [5]

Although this scientific area of research is still ongoing, and only a small number of vascular plants has been examined 95% of them partake in this symbiotic relationship with Mycorrhiza^[7]

Contents 1 Endomycorrihza 1.1 Habitat 1.2 Reproduction and Growth 1.2.1 Life Cycle 1.2.2 Nutrient Exchange 1.3 Applications 1.3.1 Genetics 1.3.2 Current Research 2 Ectomycorrihza 2.1 Habitat 2.2 Host Plant-Fungal Interactions 2.2.1 Association 2.2.2 Communication 2.2.3 Nutrient Exchange 2.3 Reproduction 3 Economic Importance 3.1 Agriculture 3.1.1 Organic Farming 3.1.2 Truffles 4 Comparison Table 5 Environmental impacts and concerns 5.1 Forest connections 5.2 Acid Rain 6 Timeline 7 Additional Information 8 References

Endomycorrihza

Endomycorrizha are also known as arbuscular mycorrihizal (AM) fungi and are generally classified in the Zygomycota phylum^[8]. However, AM fungi lack the production of zygospores, which is a main and common characteristic of all fungi within Zygomycota. Therefore, according the AFTOL, AM fungi are apart of the Glomeromycota phylum^[8]. The Gloeromycota phylum contains 12 genra and 169 species^[8].Some of the other characteristics that define Glomeromycota are formation of arbuscules in plant roots and non-septate hypahe Previously mentioned, the AM fungi are characterized within the Glomeromycota because of their relatively large multi-nucleated spores that range from 40-800µm in diameter^[8]. These spores may be formed singly, in clusters or in fruiting bodies called sporocarps^[9].

Fungal arbuscules growing inside a living plant cell.[10]

Section of a sporocarp of Glomus sinuosum (isolate MD126, formerly Sclerocystis sinuosa). Spores are arranged around a center of interwoven hyphae and covered by a "peridium".[11]

Scientific Name Glomus sp. S328 Comments Spore of Glomus sp. S328 with attached hypha. Size Spore diameter is approximately 80 µm.[12]

Habitat

Endomycorrihzae grow naturally in the North American, however, can be transplanted and utilized in areas where there is a massive decline in soil nutrients. In these conditions, AM fungi are more than often placed in poor soil conditions to aid in the growth and development of vegetation, more so agricultural crops^[8].Moreover, Endomycorrihza can be considered as ecologically important for most vascular plants and is found in 85% of plant families, most of them being crop species^{[13] [14]}

Reproduction and Growth

Life Cycle

To date, there is no evidence that proves that AM fungi produce sexually. Molecular genetic markers show that there is little to no recombination from different lineages, therefore supporting the notion that AM fungi reproduce asexually^[8]. The starting point of the AM fingi life cycle is the germination of the spore, which then either grows infection structures known as appresoria within the host plants' root system or grows hyphae from root to explore soil in order to uptake nitrogen. The appresoria move on the surface of host roots and forms hyphae between cells that penetrate cell walls ^[16]. This is the main reasons why AM fungi are not detrimental to the host plant because the hyphae grow only within the external membrane. These hyphae form coils or tree-like structures called arbuscules.

Nutrient Exchange

Endomycorrizhae have the ability to move carbon and nitrogen and utilize these molecules as an energy source.Carbon is transferred from the host plant to the internal mycelium of fungus in the form of hexose. Once within the fungi, hexose is then rearrange into glycogen and trehalose for short term storage. Then these forms of carbon are reconfigured into triacylglycerol (TAG) to be exported to the external mycelium system. TAG is then catabolized to be used at cell wall components via the glyoxylate cycle or as energy via the TCA cycle by the formation of ATP and amino acids. In this case, the fungi is using the host to benefit its’ growth.

However, when it comes to nitrogen, it functions in the opposite direction of the carbon flow. Inorganic nitrogen in the forms of ammonia (NH4+)and nitrate (NO3-) are absorbed by the external mycelium. These forms of nitrogen are not usable, thus they are assimilated and converted into Arginine; it is hypothesized that polyphosphate aids in this conversion. Arginine is then imported to the internal mycelium and catabolized further into [http:en.wikipedia.org/wiki/ammonium ammonium] (NH3+). Ammonium is a usable form of nitrogen for the fungus as well as the host plant. Ammonium is able to undergo many other chemical reactions and transformations that result in the production of ATP and amino acids. These end products are then, mainly, used by the host plant. In this case, the host plant is using the fungi to benefit its’ growth.

Diagram depicting the uptake, flow and utilization of nitrogen by AM fungi and host plant.[17]

Diagram depicting the uptake, flow and utilization of carbon by host plant to AM fungi.[18]

Applications

Dr. Gail Wilson, an Associate Professor of Natural Resource Ecology and Management, describes how beneficial mycorhizzae are for plant life. Dr. Wilson also provides an application of the mycrohizzae in rejuvenation of vegetation around areas were coal mines were present. Moreover, that the success of the transplant of pine tree to Costa Rico were dependent on the soil from North America, which contain mycorhizzae; AM fungi are only found naturally in North America.

Genetics

Current Research

STILL WORKING ON THIS SECTION (SHALINA) • One popular field is the documentation and preservation and characterization of mycorrhizal germiplasm • To develop ROC (root organ culture) of different arbuscular mycorrhizal (AM) fungi and their mass inoculum production under invitro conditions • Use as a Bio-diesel • Utilization and reclipation of industry created wasteland

Ectomycorrihza

Ectomycorrhizal (ECM) symbiosis represents one of the most prominent and ecologically crucial mutualistic associations in terrestrial habitats. These fungi evolved from humus and wood saprotrophic ancestors^[19]. Approximately 7,750 ECM fungal species are grouped within the phyla Basidiomycota, Ascomycota, and Zygomycota. However, it has been estimated that there could potentially be between 20,000 and 25,000 ECM fungal species^[20]. Approximately 6,000 plant species have been identified that also take part in the symbiotic relationship^[19].

Habitat

Ectomycorrhizas are the most advanced symbiotic association, where the fungi completely surrounds the root systems of vascular plants. Ectomycorrhizal association occurs with thousands of mostly woody plant species worldwide such as birches, oaks, and pines, where they play an important role in seedling establishment and tree growth in habitats across the globe^[20]. Ectomycorrhizal fungal species exist in most of the temperate, boreal, and Mediterranean forests of the Northern Hemisphere and parts of South America, seasonal savanna and rain forest habitats in Africa, India and Indo-Malay. They have also been found to exist in temperate rain forest and seasonal woodland communities of Australia^{[19] [22]}.

Host Plant-Fungal Interactions

Association

ECM fungi are capable of different levels of specialization with plant hosts. Some ECM fungi, such as Amanita muscari, are generalists, as they associate with a phylogenetically broad range of hosts, while others are specialized, such as those of the genera Rhizopogon, to a phylogenetically narrow range of hosts^[23]. Associations with specialized fungi reduce the chances of indirectly helping competing plant species, while generalist ECM fungi can connect individuals of hosts from the same or different species and are able to translocate carbon between hosts ^[23]. It is common to find mycorrhizas belonging to several different fungi on the root system of a single tree ^[8].

ECM fungi begin development and association with plant hosts when their hyphae infect the secondary or tertiary roots systems. Once the fungi infect the host’s roots, the hyphae grows back up the root system between the epidermal and cortical cells, both mechanically and through the excretion of pectinases, thus forming the Hartig net. It should be noted that the hyphae never penetrate into the cells, but instead the intercellular Hartig net forms completely around each cell. In this association, the fungi form a sheath of tissue, ranging in thickness between 50-100 μm around the entire root system, which provides the main interface for exchange of substances between plant and the fungi^[8].

Communication

The ECM symbiosis triggers key developmental programs in both symbionts, where the fungi must have the ability to recognize and become associated with its host, escape the host defense mechanisms, and establish bi-directional nutrient transfer^[24]. Multiple signal and communication genes are involved in a series of complex and overlapping developmental processes in the symbionts, which include switching off of fungal growth mode, initiation of lateral roots, aggregation of hyphae, arrest of cell division in ensheathed roots, and radial elongation of epidermal cells^[24]. Fungal and plant interactions are also influenced by environmental conditions, such as climate, soil, and nutrient availability, which can either enhance or repress the establishment of the symbiotic relationship^[8]. The entire purpose of development in ECM symbiosis is to extend the function of the root system^[24].

There have been a number of molecules that have been found that control the complex symbiotic interactions (communication) between the host plant and fungi, which are classified as follows^[24]:

• Rhizospheric signals (flavonoids, diterpenes, hormones and various nutrients) secreted by the plant host into the rhizosphere, a narrow region of soil directly around the root hairs, which act to modify hyphal morphology.
• Adhesins and hydrolases secreted by the hyphae and used for attachment and invasion of host plant tissues.
• Hormones and secondary signals used in the induction of organogenetic programmes in both fungal and root cells.
• Molecules that facilitate fungal survival in response to plant defense systems.
• Molecules that coordinate strategies for exchanging carbon and other metabolites between the symbionts.

Nutrient Exchange

The most important communication between plant and fungus in ectomycorrhizal association is nutrient exchange. Metabolite exchange is essential for the persistence of both plant and fungus. Nutrient exchange between the two partners depends on one partner releasing nutrients into the apoplastic interface, within the plant cell wall, followed by the other partner taking up and utilizing the specific nutrient from the interface^[8].

The majority of ectomycorrhizal fungi rely on the plant host for carbon sources due to their uncompetitive nature and inability to utilize cellulose and lignin ^[8]. The plant transfers rich carbon sources in the form of photosynthetic carbohydrates to the fungi, which the fungi use in the development of extensive hyphal growth into the soil. The plant host delivers these carbon sources to the apoplast through hydrolysis of sucrose by invertase enzyme, which produces six-carbon monosaccharides, called hexoses, that can be taken up by the fungal cells and utilized for growth and other fungal activities^[25].

Likewise, host plants rely on the fungi for the capture of some nutrients such as phosphate (P), nitrate (NO₃^-), ammonium (NH₄⁺), peptides, amino acids and potassium ions (K⁺), which the host’s root systems cannot access in the soil^[25]. Fungi are capable of harvesting inorganic phosphate (P_i) from the environment through the aid of ectoenzymes, like phosphatases, which the hyphae then deliver to the apoplast interface and are subsequently taken up by the host plant^[25]. Nitrate, ammonium, peptides and potassium ions are also taken up by the fungi through specific systems, which are converted into amino acids and transferred to the host plant through the apoplast^[25]. The fungi also confers pathogen resistance and provides protection from water stress to the plant host^[8]. Thus, this association greatly enhances mineral uptake and protection for the host plant; while at the same time provides a carbon source used by the fungus for growth.

Reproduction

Unlike fungi that form arbuscular and ericoid mycorrhizas, ECM fungi are capable of sexual reproduction where they develop fruiting bodies either above ground (epigeous, mushroom-like), or below ground (hypogeous, truffle-like), and produce thousands to millions of meiotic spores^[26].

Compared to other fungal groups, it is very rare for ECM fungi to produce asexual spores. Instead, ECM fungi only utilize asexual propagation for the vegetative spread of mycelium in the soil, or through mycelium dispersal by mycophageous organisms. Their vegetative thallus is a mycelium that has been found to span large areas. For example, in different species of Suillus, the mycelium have been found to span up to 300 m^{2 [26]}.

Economic Importance

Agriculture

The majority of higher plants exist in some sort of symbiotic relationship with mycorrhiza connections with either Endomycorrihza, Ectomycorrhizal fungi. The most widely used fungi in agricultural development are part of the endomycorrihza family, many agricultural companies sell inoculant for use in fields such as Glomus intraradices. This is especially important in agriculture as many farmers employ fungi inoculation of the root system a key part of development of their crops. These fungi improve nutrient uptake and help to optimize fertilizer, water uptake and can also restore degraded soil, cutting a farmers costs ^[27]. Endomycorrihza fungi can increase water absorption and can absorb all 15 essential micro and macro nutrients essential for plant growth and development especially in areas of low soil quality ^[28] . Mycorrhizae fungi can also provide disease protection against necrotrophic competing fungi, insects and increased resistance to salinity and heavy metals in the soil ^[29] . Many modern farming practices however do not encourage the use of endomycorrihza fungi, many modern practices are actually detrimental to soil fungal population. The use of biocides, monocultures, constant tilling and high amounts of fertilizer in the soil can have negative impacts on many endomycorrihza communities ^[30] . In an example of this a study was conducted in a monoculture soybean field with high fertilizer use, it was noted that high levels of phosphorous from constant fertilization was seen to inhibit endomycorrihza infection. Large summer fallow periods associated with monocultures in which the land is left deliberately bare were seen to decimate endomycorrihza, which cannot survive without a host plant ^[31] .

Organic Farming

The practice of organic farming generally excludes the use of harsh pesticides and fertilizer use, organic farmers abide by the guidelines of the International Federation of Organic Agricultural Movement ^[32] . Because of these guidelines many organic fields have lower phosphorous and nitrogen concentration in the soil, have lower crop yields and are more prone to pests ^[33]. In organic farms phosphorus is usually the limiting factor of crop growth, not enough is available in the soil through weathering and other natural processes. Many farmers must use a complex mix of rotting material and manure in order to increase the nutrient value of the soil, endomycorrihza inoculation of crops helps to better utilize these nutrients and increases the yield on an organic farm. ^[33] Low yield of an organic farm is one of the major downfalls to this method of farming when compared to traditional practices, therefore increasing crop yield is one of the biggest challenges facing organic farmers today. Certain species of endomycorrihza have been shown to increase growth rates of plants by stimulating the release of certain plant growth hormones such as cytokinins and gibberellins ^[33]

Truffles

Truffles have been a prized delicacy in Europe dating back to ancient Greek and Roman civilizations being recorded as early as 20 AD ^[34]. Truffle fungi form complex ectomycorrhizal relationships with host root systems of various trees such as oak, hazel and certain species of shrubs; the hyphae eventually aggregate forming an ascoma or fruiting body ^[34]. The most prized truffles come from the genus tuber, and are the “black truffle” Tuber melanosporum, and the rarer “white truffle” Tuber magnatum which can cost anywhere from 300–400 Euros per 100g ^[34].Large scale mycorrhizal production of certain species of black truffles such as Tuber melanosporum, have been produced artificially for hundreds of years. At present almost 80% of France’s black truffles are produced from artificial truffle grounds, and have been grown as far away as the United States and Israel^[34]. Artificial truffle farming is similar to fruit farming; only the fruit appears underground rather than on the tree. Tuber melanosporum is used to inoculate seedling trees such as oak or hazelnut and are than planted in the ground like a normal orchard ^[34]. In contrast Tuber magnatum “white truffles” has yet to be cultivated; therefore white truffles must still be harvested traditionally in the hillsides of northern Italy and neighboring provinces.

Figure (a) shows Tuber magnatum (white truffle) mycorrhizae, Figure (b) shows Tuber magnatum Ascospores.[34]

Shows a Black truffle(Tuber melanosporum), cultivated in a host Corylus avellana plant. Melanin production is evident on microscopic view of hyphae and ascospores [35]

A black truffle farm in Charente, France. [36]

Comparison Table

Environmental impacts and concerns

Forest connections

Mycorrhiza applications go far beyond just nutrient and water absorption and play a larger role in the forest community. Networks of Mycorrhiza can connect two trees of a different or similar species together forming vast networks throughout the forest floor ^[38]. Most forests are interconnected through these networks of mycorrhiza with the oldest trees forming the central hub of the network while the younger trees and seedlings become established in these pre made networks ^[38]. The underground networks actually help support saplings and younger weaker trees as carbon, nitrogen, water and other nutrients can be transferred through these networks from older more established trees ^[38] . This transfer of nutrients back and forth throughout the forest floor can help these systems cope with climate changes such as unusually dry conditions.

Acid Rain

Acid rain is formed in the upper atmosphere as NO and SO2 are hydrolyzed ^[39] mixing with rain water and eventually falling back down to earth. Mycorrhizal associations can be affected either indirectly through influence on host shoots, or directly by changes in soil PH. ^[40] Usually mycorrhizal fungi are either absent or show less diversity in soils with a lowered PH.^[40] Acid rain can have differing effects on different species, one particular ectomycorrhiza fungi ascomycetes Cenococcum, has been reported to be more abundant in forests that have under gone acidification, most likely due to decreased competition from other species of fungi.^[40] The problem of acid rain is often compounded as a decrease in PH leads to an increase in the rate that minerals dissolve such as Al,Cd, Cu, Ni, Pb and Zn, these heavy metals have been shown to greatly reduce the rate of mycorrhizal infection. ^[40] High aluminum concentrations have been shown to have detrimental effects on ectomycorrhiza fungi; causing massive cytoplasmic damage, affected ectomycorrhiza fungi were often also absent a Hartig net.^[40].

Management strategies for decreasing soil acidification [41]

Timeline

WORKING ON THIS PART (SHALINA) • Today scientists/mycologists are well versed in the function of arbuscular mycorrhizas and their consequences for nutrient cycling and plant prodeuctivity. They have stated their relevance in the botany and ecology. • They had a controversial linkage to the veneficial effectos of composting in inida according to Howard 1940, andwere known as “mal aimee des microbiologists” by Bertrand 1972 • 35 years ago this field of research had become reputable and 127 years after whats considered to be the first description of a mycorrhiza (Nageli 1842) • This was a large thing because of the obligate symbiotic nature of the arbuscular mycorrhizal fungi. • Arbuscular mycorrhizas were described as early as 1842 which were done by Nageli. Trappe and Berch (1985) and rayner (1926-1927) cited earlier observations of the symbiosis during the period of 1875 and 1895 • 1889 Schlicht observed the basic anatomical relationships between host and fungal tissues • 1897 Janse called the intramatrical spores “vesicules” and determined that other structures named “arbuscules by Gallaud in 1905, which were located in the inner cortex • Using transmission electron microscopy cox and sanders confirmed that it is surrounded by a host membrane in 1974 • Past techniques included cutting root systems into small pieces and determining the proportion of the pieces that were mycorrhizal, today the technique used is based on the line intersect technique devised by Newman 1966 which was applied to mycorrhizas in 1975 • There was later confusion in terms of wheher it was ectomycorrhizas and arbuscular mycorrhizas in 1927

Additional Information

Plant species that benefit from Endomycorrizha and Ectomycorrizha[1]

References

1. ↑ Frank, A. B. (1885). "Über die auf Würzelsymbiose beruhende Ehrnährung gewisser Bäum durch unterirdische Pilze". Berichte der Deutschen Botanischen Gesellschaft 3: 128–145.
2. ↑ Kirk, P. M.; Cannon, P. F.; David, J. C. & Stalpers, J. (2001). Ainsworth and Bisby’s Dictionary of the Fungi (9th ed.). Wallingford, UK: CAB International.
3. ↑ Harrison MJ (2005). "Signaling in the arbuscular mycorrhizal symbiosis". Annu Rev Microbiol. 59: 19–42. doi:10.1146/annurev.micro.58.030603.123749. PMID 16153162
4. ↑ Eco Tree Care and Conservation LTD. Mycorrhiza - The Biology A Study - What are Mycorrhiza and why are they important?http://www.ecotreecare.co.uk/mycorrhizal-inoculation-biology.htm
5. ↑ Eco Tree Care and Conservation LTD. Mycorrhiza - The Biology A Study - What are Mycorrhiza and why are they important?http://www.ecotreecare.co.uk/mycorrhizal-inoculation-biology.htm
6. ↑ Syekhfani, Prof. Dr. Ir. MS. (2013). Succession Life on Earth. Soil-Function
7. ↑ Trappe, J. M. (1987). Phylogenetic and ecologic aspects of mycotrophy in the angiosperms from an evolutionary standpoint. Florida: CRC Press.
8. ↑ ^{8.00 8.01 8.02 8.03 8.04 8.05 8.06 8.07 8.08 8.09 8.10 8.11 8.12 8.13} Moore, D., Robinsion, G.D., & Trinci, A.P. (2011) 21st Century Guidebook to Fungi. Cambridge University Press, New York.
9. ↑ Redecker, Dirk. 2008. Glomeromycota. Arbuscular mycorrhizal fungi and their relative(s). Version 14 January 2008. http://tolweb.org/Glomeromycota/28715/2008.01.14 in The Tree of Life Web Project, http://tolweb.org/
10. ↑ http://shachar-hill.plantbiology.msu.edu/?page_id=44
11. ↑ Photo © Dirk Redecker, isolate courtesy of J. B. Morton at INVAM. Sporocarp diameter approximately 250 µm.
12. ↑ Copyright © 2000 American Association for the Advancement of Science Image Use restricted Attached to Group Glomeromycota: view page image collection Title s328_small.jpg Image Type Photograph Image Content Specimen(s) ID 7350 http://tolweb.org/Glomeromycota .
13. ↑ Gederman, H. A. Rev. Phytopath. 6, 397−418 (1968).
14. ↑ Wang, B.; Qiu, Y.L. (2006). "Phylogenetic distribution and evolution of mycorrhizas in land plants". Mycorrhiza 16 (5): 299–363. doi:10.1007/s00572-005-0033-6. PMID 16845554. Retrieved 2008-01-21.
15. ↑ http://shachar-hill.plantbiology.msu.edu/?page_id=44
16. ↑ Shchar-hil Lab doi:http://shachar-hill.plantbiology.msu.edu/?page_id=44
17. ↑ http://shachar-hill.plantbiology.msu.edu/?page_id=44
18. ↑ http://shachar-hill.plantbiology.msu.edu/?page_id=44
19. ↑ ^{19.0 19.1 19.2} Tedersoo, L., May, T.W., & Smith, M.E. (2010). Ectomycorrhizal lifestyle in fungi: global diversity, distribution, and evolution of phylogenetic lineages. Mycorrhiza, 20, 217-263.
20. ↑ ^{20.0 20.1} Rinaldi, A.C., Comandini, O., & Kuyper, T.W. (2008). Ectomycorrhizal fungi diversity: separating the wheat from the chaff. Fungal Diversity, 33, 1-45.
21. ↑ Alberton, O., & Kuyper, T. (2009). Ectomycorrhizal fungi associated with seedlings respond differently to increased carbon and nitrogen availability: implications for ecosystem responses to global change. Global Change Biology, 15 (1), 166-175
22. ↑ Abuzinadah, R.A., & Read, D.J. (1986). The role of proteins in the nitrogen nutrition of Ectomycorrhizal plants. New Phytologist, 103, 481-493.
23. ↑ ^{23.0 23.1} den Bakker, H.C., Zuccarello, G.C., Kuyper, T.H.W., & Noordeloos, M.E. (2004). Evolution and host specificity in the ectomycorrhizal genus Leccinum. New Phyologist, 163, 201-215.
24. ↑ ^{24.0 24.1 24.2 24.3} Martin, F., Duplessis, S., Ditengou, F., Lagrange, H., Voiblet, C., & Lapeyrie, F. (2001). Developmental cross talking in the ectomycorrhizal symbiosis: signals and communication genes. New Phytologist, 151, 145-154.
25. ↑ ^{25.0 25.1 25.2 25.3} Bucking, H., Hans, R., & Heyser, W. (2007). The apoplast of ectomycorrhizal roots – site of nutrient uptake and nutrient exchange between the symbiotic partners. The Apoplast of Higher Plants: Compartment of Storage, Transport and Reactions, 1, 97-108.
26. ↑ ^{26.0 26.1} Carriconde, F., Gryta, H., Jargeat, P., Mouhamadou, B., & Gardes, M. (2008). High sexual reproduction and limited contemporary dispersal in the ectomycorrhizal fungus Tricholoma scalpturatum: new insights from population genetics and spatial autocorrelation analysis. Molecular Ecology, 17, 4433-4445.
27. ↑ Kurle, J.E and F.L. Pfleger, 1994. The Effects of Cultural Practices and Pesticides on VAM Fungi. In: Mycorrhizae and Plant Health, Pfleger, F.L. and R.G. Linderman (Eds.). APS Press, St. Paul, Minnesota, USA., pp: 101-131
28. ↑ Lester, D., 2009. Buying and applying mycorrhizal fungi. Max. Yield. USA., pp: 126-131
29. ↑ Gange, A.C., D.E. Lindsay and L.S. Ellis, 1999. Can arbuscular mycorrhizal fungi be used to control undesirable grass Poa annua on golf courses. J. Applied Ecol., 36: 909-919
30. ↑ Kabir, Z., I.P. O'Halloran, J.W. Fyles and C. Hamel, 1998. Dynamics of the Mycorrhizal symbiosis of corn (Zea mays L.): Effects of host physiology, tillage practice and fertilization on spatial distribution of extra-radical mycorrhizal hyphae in the field. Agric. Ecosyst. Environ., 68: 151-163
31. ↑ Ezawa, T., K. Yamamoto and S. Yoshida, 2000. Species composition and spore density of indigenous vesicular-arbuscular mycorrhizal fungi under different conditions of P-fertility as revealed by soybean trap culture. Soil. Sci. Plant Nutr., 46: 291-299
32. ↑ Stockdale, E.A., N.H. Lampkin, M. Hovi, R. Keatinge and E.K.M. Lennartsson et al., 2001. Agronomic and environmental implications of organic farming systems. Adv. Agron., 70: 261-262
33. ↑ ^{33.0 33.1 33.2} Mahmood, I. Rizvi, R. Mycorrhiza and organic farming. (2010) Asian Journal of Plant Sciences, 9: 241-248
34. ↑ ^{34.0 34.1 34.2 34.3 34.4 34.5} Mello, A. Murat, C. Bonfante, P. Truffles: much more than a prized and local fungal delicacy. FEMS Microbiol Lett 260 (2006) 1–8
35. ↑ Zarivi, O. Bonfigli, A. Colafarina, S. Aimola, P. Ragnelli, A. Pacioni, G. Miranda, M. Tyrosinase expression during black truffle development: From free living mycelium to ripe fruit body. Phytochemistry. Volume 72, issue 18, December 2011, pages 2317-2324
36. ↑ Sourzat, P. Black Truffle Cultivation and Competing Fungi. Proceedings of the 7th International Conference on Mushroom Biology and Mushroom Products (ICMBMP7) 2011
37. ↑ Mosquin, D. Mycorrhizal Networks.UBC Botanical Garden and Centre for Plant Research. (March 6 2010) http://www.botanicalgarden.ubc.ca/potd/2010/03/mycorrhizal_networks.php
38. ↑ ^{38.0 38.1 38.2} Beiler KJ, Durall DM, Simard SW, Maxwell SA, Kretzer AM. 2010. Architecture of the wood-wide web: Rhizopogon spp genets link multiple Douglas-fir cohorts. New Phytologist, 185: 543-553.
39. ↑ Charlson, R.J., Rodhe, H., 1982. Factors controlling the acidity of natural rainwater. Nature 295, 683-685
40. ↑ ^{40.0 40.1 40.2 40.3 40.4} Cairney,J. Meharg,A. Influences of anthropogenic pollution on mycorrhizal fungal.Environmental Pollution 106 (1999) 169-182.
41. ↑ Wortmann, C. Mamo, M. Shapiro, C. Management Strategies to Reduce the Rate of Soil Acidification. Neb Guide. University of Nebraska. February 2003. http://www.ianrpubs.unl.edu/pages/publicationD.jsp?publicationId=111